Light-driven artificial neuron models based on photoswitchable systems

Neuromorphic engineering devises and implements surrogates of neurons to contrive brain-like computing machines. This work presents the design and computational analysis of two artificial neuron models based on photochromic compounds. The first system is a model of a pacemaker neuron. It consists of two direct thermally reversible photochromic compounds that interplay mutually through inner optical filter effects. The two photochromic compounds give rise to oscillations if they have specific spectral and dynamical properties. The second system consists of three thermally reversible photochromic compounds. They interact through a structure of negative feedback actions based on the inner filter effect, which mimics the chemical relationships established between the three genes involved in the biochemical “Repressilator”. Hence, this system is named “Optical Repressilator”. For specific chemical composition and values of the parameters characterizing the photochromic compounds, it is a valuable model of a phasic photo-excitable neuron.